The technical domain of the invention relates to laboratory instruments, particularly laboratory pipettes, and specifically single-use disposable pipettes used in biology laboratories, medical analyses, serology, immunology, microbiology and industrial laboratories, etc.
It is known that different volume pipettes are not very different from each other. Thus, when many pipettes with different volumes are mixed together, it is very difficult to distinguish between them, particularly when a large number of manipulations is necessary, or if the manipulations have to be made quickly.
Different proposals according to prior art are intended to supply laboratory pipettes that can be quickly and unambiguously identified in terms of their main characteristic and particularly their nominal volume. It is then possible to immediately choose a pipette with a given characteristic among a group of pipettes with various characteristics. European patent EP 261 023 proposes a laboratory pipette of the type comprising characterisation means such that the user can immediately identify a maximum or nominal volume of the pipette without any possible error, characterised in that the characterisation means comprise at least one piece of coloured material in a colour corresponding to the maximum or nominal volume of the pipette and that is inserted in the suction end of the pipette. The piece of coloured material forms a reliable characterisation means with a very low cost price visible to the user from the outside under all circumstances, while remaining unaffected by any external aggression. In general, a colour code is used complying with the international standard with a bi-univocal relation with the maximum or nominal volumes of frequently used pipettes. For example, this standard specifies that 1 ml pipettes are characterised by yellow, 2 ml pipettes by green, 5 ml pipettes by blue, 10 ml pipettes by orange, 25 ml pipettes by red, etc.